Our understanding of the biological changes in the brain associated with Alzheimer's disease (AD) pathology and cognitive impairment remains incomplete. To increase our understanding of these changes, we analyzed dorsolateral prefrontal cortex of control, asymptomatic AD, and AD brains from four different centers by label-free quantitative mass spectrometry and weighted protein co-expression analysis to obtain a consensus protein co-expression network of AD brain. This network consisted of 13 protein co-expression modules. Six of these modules correlated with amyloid-β plaque burden, tau neurofibrillary tangle burden, cognitive function, and clinical functional status, and were altered in asymptomatic AD, AD, or in both disease states. These six modules reflected synaptic, mitochondrial, sugar metabolism, extracellular matrix, cytoskeletal, and RNA binding/splicing biological functions. The identified protein network modules were preserved in a community-based cohort analyzed by a different quantitative mass spectrometry approach. They were also preserved in temporal lobe and precuneus brain regions. Some of the modules were influenced by aging, and showed changes in other neurodegenerative diseases such as frontotemporal dementia and corticobasal degeneration. The module most strongly associated with AD pathology and cognitive impairment was the sugar metabolism module. This module was enriched in AD genetic risk factors, and was also highly enriched in microglia and astrocyte protein markers associated with an anti-inflammatory state, suggesting that the biological functions it represents serve a protective role in AD. Proteins from the sugar metabolism module were increased in cerebrospinal fluid from asymptomatic AD and AD cases, highlighting their potential as biomarkers of the altered brain network. In this study of >2000 brains and nearly 400 cerebrospinal fluid samples by quantitative proteomics, we identify proteins and biological processes in AD brain that may serve as therapeutic targets and fluid biomarkers for the disease.

Cerebral atherosclerosis contributes to dementia via unclear processes. We performed proteomic sequencing of dorsolateral prefrontal cortex in 438 older individuals and found associations between cerebral atherosclerosis and reduced synaptic signaling and RNA splicing and increased oligodendrocyte development and myelination. Consistently, single-cell RNA sequencing showed cerebral atherosclerosis associated with higher oligodendrocyte abundance. A subset of proteins and modules associated with cerebral atherosclerosis was also associated with Alzheimer’s disease, suggesting shared mechanisms.

In the Intraoperative Hypothermia for Aneurysm Surgery Trial, neither systemic hypothermia nor supplemental protective drug affected short- or long-term neurologic outcomes of patients undergoing temporary clipping.

Objective Identify methods to improve the frozen-section diagnosis of acute invasive fungal rhinosinusitis. Study Design Biopsies with frozen section for suspected acute invasive fungal rhinosinusitis were reviewed to identify causes for missed diagnoses and evaluate methods for potential improvement. Setting All aspects of the study were performed at the Penn State Milton S. Hershey Medical Center. Subjects and Methods All frozen sections performed for suspected acute invasive fungal rhinosinusitis between 2006 through 2017 were reviewed with their diagnoses compared to the final diagnoses. Sensitivity and specificity were determined for each biopsy specimen to evaluate the diagnostic method and for each patient for its effectiveness on outcome. Causes for frozen-section failures in diagnosis were identified. A periodic acid-Schiff stain for fungus (PASF) was modified for use on frozen tissue (PASF-fs) and applied both retrospectively and prospectively to frozen sections to determine its ability to identify undetected fungus and improve diagnostic sensitivity. Results Of 63 biopsies positive for acute invasive fungal rhinosinusitis, 51 were diagnosed on frozen section, while 61 were identified by including the novel PASF-fs stain, reducing the failure rate from 19% to 3%. Of 41 cases that were positive, 34 were diagnosed on frozen section. Of the 7 that were not, 5 were identified by including the PASF-fs, reducing the failure rate from 17% to 5%. Conclusions Frozen section interpretation of biopsies for suspected acute invasive fungal rhinosinusitis using a PASF-fs stain should enable a rapid and accurate diagnosis with improved outcomes by shortening the time to surgery.

Our understanding of the biological changes in the brain associated with Alzheimer's disease (AD) pathology and cognitive impairment remains incomplete. To increase our understanding of these changes, we analyzed dorsolateral prefrontal cortex of control, asymptomatic AD, and AD brains from four different centers by label-free quantitative mass spectrometry and weighted protein co-expression analysis to obtain a consensus protein co-expression network of AD brain.This network consisted of 13 protein co-expression modules. Six of these modules correlated with amyloid-β plaque burden, tau neurofibrillary tangle burden, cognitive function, and clinical functional status, and were altered in asymptomatic AD, AD, or in both disease states. These modules reflected synaptic, mitochondrial, sugar metabolism, extracellular matrix, cytoskeletal, and RNA binding/splicing biological functions. The identified protein network modules were preserved in a community-based cohort analyzed by a different quantitative mass spectrometry approach. They were also preserved in temporal lobe and precuneus brain regions. Some of the modules were influenced by aging, and showed changes in other neurodegenerative diseases such as frontotemporal dementia and corticobasal degeneration. The module most strongly associated with AD pathology and cognitive impairment was the sugar metabolism module, which was enriched in AD genetic risk factors and correlated with APOE genetic risk. This module was also highly enriched in microglia and astrocyte protein markers associated with an antiinflammatory state, suggesting that the biological functions it represents serve a protective role in AD. Proteins from this module were increased in cerebrospinal fluid from asymptomatic AD and AD cases, highlighting their potential as biomarkers of the altered brain network. In this study of >2000 brains and nearly 400 cerebrospinal fluid samples by quantitative proteomics, we identify proteins and biological processes in AD brain that may serve as therapeutic targets and fluid biomarkers for the disease. IntroductionAlzheimer's disease (AD) is a leading cause of death worldwide, with increasing prevalence as global life expectancy increases 1 . Although AD is currently defined on the basis of amyloid-β plaque and tau neurofibrillary tangle deposition within the neocortex 2 , the biochemical and cellular changes in the brain that characterize the disease beyond amyloid-β and tau deposition remain incompletely understood. The genetic architecture of late-onset AD has been extensively studied, and the results of these studies implicate multiple biological pathways that contribute to development of the disease, including immune function, endocytic vesicle trafficking, and lipid homeostasis, among others 3-5 . In addition to genetic studies, transcriptomic studies on postmortem AD brain tissue have identified changes in mRNA co-expression that correlate with disease traits and cognitive decline 6,7 . However, given that mRNA levels correlate only modestly to protein le...